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1/* Helpers for initial module or kernel cmdline parsing
2 Copyright (C) 2001 Rusty Russell.
3
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2 of the License, or
7 (at your option) any later version.
8
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
13
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17*/
18#include <linux/moduleparam.h>
19#include <linux/kernel.h>
20#include <linux/string.h>
21#include <linux/errno.h>
22#include <linux/module.h>
23#include <linux/device.h>
24#include <linux/err.h>
25#include <linux/slab.h>
26#include <linux/ctype.h>
27
28#if 0
29#define DEBUGP printk
30#else
31#define DEBUGP(fmt, a...)
32#endif
33
34/* Protects all parameters, and incidentally kmalloced_param list. */
35static DEFINE_MUTEX(param_lock);
36
37/* This just allows us to keep track of which parameters are kmalloced. */
38struct kmalloced_param {
39 struct list_head list;
40 char val[];
41};
42static LIST_HEAD(kmalloced_params);
43
44static void *kmalloc_parameter(unsigned int size)
45{
46 struct kmalloced_param *p;
47
48 p = kmalloc(sizeof(*p) + size, GFP_KERNEL);
49 if (!p)
50 return NULL;
51
52 list_add(&p->list, &kmalloced_params);
53 return p->val;
54}
55
56/* Does nothing if parameter wasn't kmalloced above. */
57static void maybe_kfree_parameter(void *param)
58{
59 struct kmalloced_param *p;
60
61 list_for_each_entry(p, &kmalloced_params, list) {
62 if (p->val == param) {
63 list_del(&p->list);
64 kfree(p);
65 break;
66 }
67 }
68}
69
70static inline char dash2underscore(char c)
71{
72 if (c == '-')
73 return '_';
74 return c;
75}
76
77static inline int parameq(const char *input, const char *paramname)
78{
79 unsigned int i;
80 for (i = 0; dash2underscore(input[i]) == paramname[i]; i++)
81 if (input[i] == '\0')
82 return 1;
83 return 0;
84}
85
86static int parse_one(char *param,
87 char *val,
88 const struct kernel_param *params,
89 unsigned num_params,
90 int (*handle_unknown)(char *param, char *val))
91{
92 unsigned int i;
93 int err;
94
95 /* Find parameter */
96 for (i = 0; i < num_params; i++) {
97 if (parameq(param, params[i].name)) {
98 /* No one handled NULL, so do it here. */
99 if (!val && params[i].ops->set != param_set_bool)
100 return -EINVAL;
101 DEBUGP("They are equal! Calling %p\n",
102 params[i].ops->set);
103 mutex_lock(¶m_lock);
104 err = params[i].ops->set(val, ¶ms[i]);
105 mutex_unlock(¶m_lock);
106 return err;
107 }
108 }
109
110 if (handle_unknown) {
111 DEBUGP("Unknown argument: calling %p\n", handle_unknown);
112 return handle_unknown(param, val);
113 }
114
115 DEBUGP("Unknown argument `%s'\n", param);
116 return -ENOENT;
117}
118
119/* You can use " around spaces, but can't escape ". */
120/* Hyphens and underscores equivalent in parameter names. */
121static char *next_arg(char *args, char **param, char **val)
122{
123 unsigned int i, equals = 0;
124 int in_quote = 0, quoted = 0;
125 char *next;
126
127 if (*args == '"') {
128 args++;
129 in_quote = 1;
130 quoted = 1;
131 }
132
133 for (i = 0; args[i]; i++) {
134 if (isspace(args[i]) && !in_quote)
135 break;
136 if (equals == 0) {
137 if (args[i] == '=')
138 equals = i;
139 }
140 if (args[i] == '"')
141 in_quote = !in_quote;
142 }
143
144 *param = args;
145 if (!equals)
146 *val = NULL;
147 else {
148 args[equals] = '\0';
149 *val = args + equals + 1;
150
151 /* Don't include quotes in value. */
152 if (**val == '"') {
153 (*val)++;
154 if (args[i-1] == '"')
155 args[i-1] = '\0';
156 }
157 if (quoted && args[i-1] == '"')
158 args[i-1] = '\0';
159 }
160
161 if (args[i]) {
162 args[i] = '\0';
163 next = args + i + 1;
164 } else
165 next = args + i;
166
167 /* Chew up trailing spaces. */
168 return skip_spaces(next);
169}
170
171/* Args looks like "foo=bar,bar2 baz=fuz wiz". */
172int parse_args(const char *name,
173 char *args,
174 const struct kernel_param *params,
175 unsigned num,
176 int (*unknown)(char *param, char *val))
177{
178 char *param, *val;
179
180 DEBUGP("Parsing ARGS: %s\n", args);
181
182 /* Chew leading spaces */
183 args = skip_spaces(args);
184
185 while (*args) {
186 int ret;
187 int irq_was_disabled;
188
189 args = next_arg(args, ¶m, &val);
190 irq_was_disabled = irqs_disabled();
191 ret = parse_one(param, val, params, num, unknown);
192 if (irq_was_disabled && !irqs_disabled()) {
193 printk(KERN_WARNING "parse_args(): option '%s' enabled "
194 "irq's!\n", param);
195 }
196 switch (ret) {
197 case -ENOENT:
198 printk(KERN_ERR "%s: Unknown parameter `%s'\n",
199 name, param);
200 return ret;
201 case -ENOSPC:
202 printk(KERN_ERR
203 "%s: `%s' too large for parameter `%s'\n",
204 name, val ?: "", param);
205 return ret;
206 case 0:
207 break;
208 default:
209 printk(KERN_ERR
210 "%s: `%s' invalid for parameter `%s'\n",
211 name, val ?: "", param);
212 return ret;
213 }
214 }
215
216 /* All parsed OK. */
217 return 0;
218}
219
220/* Lazy bastard, eh? */
221#define STANDARD_PARAM_DEF(name, type, format, tmptype, strtolfn) \
222 int param_set_##name(const char *val, const struct kernel_param *kp) \
223 { \
224 tmptype l; \
225 int ret; \
226 \
227 ret = strtolfn(val, 0, &l); \
228 if (ret < 0 || ((type)l != l)) \
229 return ret < 0 ? ret : -EINVAL; \
230 *((type *)kp->arg) = l; \
231 return 0; \
232 } \
233 int param_get_##name(char *buffer, const struct kernel_param *kp) \
234 { \
235 return sprintf(buffer, format, *((type *)kp->arg)); \
236 } \
237 struct kernel_param_ops param_ops_##name = { \
238 .set = param_set_##name, \
239 .get = param_get_##name, \
240 }; \
241 EXPORT_SYMBOL(param_set_##name); \
242 EXPORT_SYMBOL(param_get_##name); \
243 EXPORT_SYMBOL(param_ops_##name)
244
245
246STANDARD_PARAM_DEF(byte, unsigned char, "%c", unsigned long, strict_strtoul);
247STANDARD_PARAM_DEF(short, short, "%hi", long, strict_strtol);
248STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", unsigned long, strict_strtoul);
249STANDARD_PARAM_DEF(int, int, "%i", long, strict_strtol);
250STANDARD_PARAM_DEF(uint, unsigned int, "%u", unsigned long, strict_strtoul);
251STANDARD_PARAM_DEF(long, long, "%li", long, strict_strtol);
252STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", unsigned long, strict_strtoul);
253
254int param_set_charp(const char *val, const struct kernel_param *kp)
255{
256 if (strlen(val) > 1024) {
257 printk(KERN_ERR "%s: string parameter too long\n",
258 kp->name);
259 return -ENOSPC;
260 }
261
262 maybe_kfree_parameter(*(char **)kp->arg);
263
264 /* This is a hack. We can't kmalloc in early boot, and we
265 * don't need to; this mangled commandline is preserved. */
266 if (slab_is_available()) {
267 *(char **)kp->arg = kmalloc_parameter(strlen(val)+1);
268 if (!*(char **)kp->arg)
269 return -ENOMEM;
270 strcpy(*(char **)kp->arg, val);
271 } else
272 *(const char **)kp->arg = val;
273
274 return 0;
275}
276EXPORT_SYMBOL(param_set_charp);
277
278int param_get_charp(char *buffer, const struct kernel_param *kp)
279{
280 return sprintf(buffer, "%s", *((char **)kp->arg));
281}
282EXPORT_SYMBOL(param_get_charp);
283
284static void param_free_charp(void *arg)
285{
286 maybe_kfree_parameter(*((char **)arg));
287}
288
289struct kernel_param_ops param_ops_charp = {
290 .set = param_set_charp,
291 .get = param_get_charp,
292 .free = param_free_charp,
293};
294EXPORT_SYMBOL(param_ops_charp);
295
296/* Actually could be a bool or an int, for historical reasons. */
297int param_set_bool(const char *val, const struct kernel_param *kp)
298{
299 bool v;
300 int ret;
301
302 /* No equals means "set"... */
303 if (!val) val = "1";
304
305 /* One of =[yYnN01] */
306 ret = strtobool(val, &v);
307 if (ret)
308 return ret;
309
310 if (kp->flags & KPARAM_ISBOOL)
311 *(bool *)kp->arg = v;
312 else
313 *(int *)kp->arg = v;
314 return 0;
315}
316EXPORT_SYMBOL(param_set_bool);
317
318int param_get_bool(char *buffer, const struct kernel_param *kp)
319{
320 bool val;
321 if (kp->flags & KPARAM_ISBOOL)
322 val = *(bool *)kp->arg;
323 else
324 val = *(int *)kp->arg;
325
326 /* Y and N chosen as being relatively non-coder friendly */
327 return sprintf(buffer, "%c", val ? 'Y' : 'N');
328}
329EXPORT_SYMBOL(param_get_bool);
330
331struct kernel_param_ops param_ops_bool = {
332 .set = param_set_bool,
333 .get = param_get_bool,
334};
335EXPORT_SYMBOL(param_ops_bool);
336
337/* This one must be bool. */
338int param_set_invbool(const char *val, const struct kernel_param *kp)
339{
340 int ret;
341 bool boolval;
342 struct kernel_param dummy;
343
344 dummy.arg = &boolval;
345 dummy.flags = KPARAM_ISBOOL;
346 ret = param_set_bool(val, &dummy);
347 if (ret == 0)
348 *(bool *)kp->arg = !boolval;
349 return ret;
350}
351EXPORT_SYMBOL(param_set_invbool);
352
353int param_get_invbool(char *buffer, const struct kernel_param *kp)
354{
355 return sprintf(buffer, "%c", (*(bool *)kp->arg) ? 'N' : 'Y');
356}
357EXPORT_SYMBOL(param_get_invbool);
358
359struct kernel_param_ops param_ops_invbool = {
360 .set = param_set_invbool,
361 .get = param_get_invbool,
362};
363EXPORT_SYMBOL(param_ops_invbool);
364
365/* We break the rule and mangle the string. */
366static int param_array(const char *name,
367 const char *val,
368 unsigned int min, unsigned int max,
369 void *elem, int elemsize,
370 int (*set)(const char *, const struct kernel_param *kp),
371 u16 flags,
372 unsigned int *num)
373{
374 int ret;
375 struct kernel_param kp;
376 char save;
377
378 /* Get the name right for errors. */
379 kp.name = name;
380 kp.arg = elem;
381 kp.flags = flags;
382
383 *num = 0;
384 /* We expect a comma-separated list of values. */
385 do {
386 int len;
387
388 if (*num == max) {
389 printk(KERN_ERR "%s: can only take %i arguments\n",
390 name, max);
391 return -EINVAL;
392 }
393 len = strcspn(val, ",");
394
395 /* nul-terminate and parse */
396 save = val[len];
397 ((char *)val)[len] = '\0';
398 BUG_ON(!mutex_is_locked(¶m_lock));
399 ret = set(val, &kp);
400
401 if (ret != 0)
402 return ret;
403 kp.arg += elemsize;
404 val += len+1;
405 (*num)++;
406 } while (save == ',');
407
408 if (*num < min) {
409 printk(KERN_ERR "%s: needs at least %i arguments\n",
410 name, min);
411 return -EINVAL;
412 }
413 return 0;
414}
415
416static int param_array_set(const char *val, const struct kernel_param *kp)
417{
418 const struct kparam_array *arr = kp->arr;
419 unsigned int temp_num;
420
421 return param_array(kp->name, val, 1, arr->max, arr->elem,
422 arr->elemsize, arr->ops->set, kp->flags,
423 arr->num ?: &temp_num);
424}
425
426static int param_array_get(char *buffer, const struct kernel_param *kp)
427{
428 int i, off, ret;
429 const struct kparam_array *arr = kp->arr;
430 struct kernel_param p;
431
432 p = *kp;
433 for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) {
434 if (i)
435 buffer[off++] = ',';
436 p.arg = arr->elem + arr->elemsize * i;
437 BUG_ON(!mutex_is_locked(¶m_lock));
438 ret = arr->ops->get(buffer + off, &p);
439 if (ret < 0)
440 return ret;
441 off += ret;
442 }
443 buffer[off] = '\0';
444 return off;
445}
446
447static void param_array_free(void *arg)
448{
449 unsigned int i;
450 const struct kparam_array *arr = arg;
451
452 if (arr->ops->free)
453 for (i = 0; i < (arr->num ? *arr->num : arr->max); i++)
454 arr->ops->free(arr->elem + arr->elemsize * i);
455}
456
457struct kernel_param_ops param_array_ops = {
458 .set = param_array_set,
459 .get = param_array_get,
460 .free = param_array_free,
461};
462EXPORT_SYMBOL(param_array_ops);
463
464int param_set_copystring(const char *val, const struct kernel_param *kp)
465{
466 const struct kparam_string *kps = kp->str;
467
468 if (strlen(val)+1 > kps->maxlen) {
469 printk(KERN_ERR "%s: string doesn't fit in %u chars.\n",
470 kp->name, kps->maxlen-1);
471 return -ENOSPC;
472 }
473 strcpy(kps->string, val);
474 return 0;
475}
476EXPORT_SYMBOL(param_set_copystring);
477
478int param_get_string(char *buffer, const struct kernel_param *kp)
479{
480 const struct kparam_string *kps = kp->str;
481 return strlcpy(buffer, kps->string, kps->maxlen);
482}
483EXPORT_SYMBOL(param_get_string);
484
485struct kernel_param_ops param_ops_string = {
486 .set = param_set_copystring,
487 .get = param_get_string,
488};
489EXPORT_SYMBOL(param_ops_string);
490
491/* sysfs output in /sys/modules/XYZ/parameters/ */
492#define to_module_attr(n) container_of(n, struct module_attribute, attr)
493#define to_module_kobject(n) container_of(n, struct module_kobject, kobj)
494
495extern struct kernel_param __start___param[], __stop___param[];
496
497struct param_attribute
498{
499 struct module_attribute mattr;
500 const struct kernel_param *param;
501};
502
503struct module_param_attrs
504{
505 unsigned int num;
506 struct attribute_group grp;
507 struct param_attribute attrs[0];
508};
509
510#ifdef CONFIG_SYSFS
511#define to_param_attr(n) container_of(n, struct param_attribute, mattr)
512
513static ssize_t param_attr_show(struct module_attribute *mattr,
514 struct module_kobject *mk, char *buf)
515{
516 int count;
517 struct param_attribute *attribute = to_param_attr(mattr);
518
519 if (!attribute->param->ops->get)
520 return -EPERM;
521
522 mutex_lock(¶m_lock);
523 count = attribute->param->ops->get(buf, attribute->param);
524 mutex_unlock(¶m_lock);
525 if (count > 0) {
526 strcat(buf, "\n");
527 ++count;
528 }
529 return count;
530}
531
532/* sysfs always hands a nul-terminated string in buf. We rely on that. */
533static ssize_t param_attr_store(struct module_attribute *mattr,
534 struct module_kobject *km,
535 const char *buf, size_t len)
536{
537 int err;
538 struct param_attribute *attribute = to_param_attr(mattr);
539
540 if (!attribute->param->ops->set)
541 return -EPERM;
542
543 mutex_lock(¶m_lock);
544 err = attribute->param->ops->set(buf, attribute->param);
545 mutex_unlock(¶m_lock);
546 if (!err)
547 return len;
548 return err;
549}
550#endif
551
552#ifdef CONFIG_MODULES
553#define __modinit
554#else
555#define __modinit __init
556#endif
557
558#ifdef CONFIG_SYSFS
559void __kernel_param_lock(void)
560{
561 mutex_lock(¶m_lock);
562}
563EXPORT_SYMBOL(__kernel_param_lock);
564
565void __kernel_param_unlock(void)
566{
567 mutex_unlock(¶m_lock);
568}
569EXPORT_SYMBOL(__kernel_param_unlock);
570
571/*
572 * add_sysfs_param - add a parameter to sysfs
573 * @mk: struct module_kobject
574 * @kparam: the actual parameter definition to add to sysfs
575 * @name: name of parameter
576 *
577 * Create a kobject if for a (per-module) parameter if mp NULL, and
578 * create file in sysfs. Returns an error on out of memory. Always cleans up
579 * if there's an error.
580 */
581static __modinit int add_sysfs_param(struct module_kobject *mk,
582 const struct kernel_param *kp,
583 const char *name)
584{
585 struct module_param_attrs *new;
586 struct attribute **attrs;
587 int err, num;
588
589 /* We don't bother calling this with invisible parameters. */
590 BUG_ON(!kp->perm);
591
592 if (!mk->mp) {
593 num = 0;
594 attrs = NULL;
595 } else {
596 num = mk->mp->num;
597 attrs = mk->mp->grp.attrs;
598 }
599
600 /* Enlarge. */
601 new = krealloc(mk->mp,
602 sizeof(*mk->mp) + sizeof(mk->mp->attrs[0]) * (num+1),
603 GFP_KERNEL);
604 if (!new) {
605 kfree(mk->mp);
606 err = -ENOMEM;
607 goto fail;
608 }
609 attrs = krealloc(attrs, sizeof(new->grp.attrs[0])*(num+2), GFP_KERNEL);
610 if (!attrs) {
611 err = -ENOMEM;
612 goto fail_free_new;
613 }
614
615 /* Sysfs wants everything zeroed. */
616 memset(new, 0, sizeof(*new));
617 memset(&new->attrs[num], 0, sizeof(new->attrs[num]));
618 memset(&attrs[num], 0, sizeof(attrs[num]));
619 new->grp.name = "parameters";
620 new->grp.attrs = attrs;
621
622 /* Tack new one on the end. */
623 sysfs_attr_init(&new->attrs[num].mattr.attr);
624 new->attrs[num].param = kp;
625 new->attrs[num].mattr.show = param_attr_show;
626 new->attrs[num].mattr.store = param_attr_store;
627 new->attrs[num].mattr.attr.name = (char *)name;
628 new->attrs[num].mattr.attr.mode = kp->perm;
629 new->num = num+1;
630
631 /* Fix up all the pointers, since krealloc can move us */
632 for (num = 0; num < new->num; num++)
633 new->grp.attrs[num] = &new->attrs[num].mattr.attr;
634 new->grp.attrs[num] = NULL;
635
636 mk->mp = new;
637 return 0;
638
639fail_free_new:
640 kfree(new);
641fail:
642 mk->mp = NULL;
643 return err;
644}
645
646#ifdef CONFIG_MODULES
647static void free_module_param_attrs(struct module_kobject *mk)
648{
649 kfree(mk->mp->grp.attrs);
650 kfree(mk->mp);
651 mk->mp = NULL;
652}
653
654/*
655 * module_param_sysfs_setup - setup sysfs support for one module
656 * @mod: module
657 * @kparam: module parameters (array)
658 * @num_params: number of module parameters
659 *
660 * Adds sysfs entries for module parameters under
661 * /sys/module/[mod->name]/parameters/
662 */
663int module_param_sysfs_setup(struct module *mod,
664 const struct kernel_param *kparam,
665 unsigned int num_params)
666{
667 int i, err;
668 bool params = false;
669
670 for (i = 0; i < num_params; i++) {
671 if (kparam[i].perm == 0)
672 continue;
673 err = add_sysfs_param(&mod->mkobj, &kparam[i], kparam[i].name);
674 if (err)
675 return err;
676 params = true;
677 }
678
679 if (!params)
680 return 0;
681
682 /* Create the param group. */
683 err = sysfs_create_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
684 if (err)
685 free_module_param_attrs(&mod->mkobj);
686 return err;
687}
688
689/*
690 * module_param_sysfs_remove - remove sysfs support for one module
691 * @mod: module
692 *
693 * Remove sysfs entries for module parameters and the corresponding
694 * kobject.
695 */
696void module_param_sysfs_remove(struct module *mod)
697{
698 if (mod->mkobj.mp) {
699 sysfs_remove_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
700 /* We are positive that no one is using any param
701 * attrs at this point. Deallocate immediately. */
702 free_module_param_attrs(&mod->mkobj);
703 }
704}
705#endif
706
707void destroy_params(const struct kernel_param *params, unsigned num)
708{
709 unsigned int i;
710
711 for (i = 0; i < num; i++)
712 if (params[i].ops->free)
713 params[i].ops->free(params[i].arg);
714}
715
716static struct module_kobject * __init locate_module_kobject(const char *name)
717{
718 struct module_kobject *mk;
719 struct kobject *kobj;
720 int err;
721
722 kobj = kset_find_obj(module_kset, name);
723 if (kobj) {
724 mk = to_module_kobject(kobj);
725 } else {
726 mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL);
727 BUG_ON(!mk);
728
729 mk->mod = THIS_MODULE;
730 mk->kobj.kset = module_kset;
731 err = kobject_init_and_add(&mk->kobj, &module_ktype, NULL,
732 "%s", name);
733#ifdef CONFIG_MODULES
734 if (!err)
735 err = sysfs_create_file(&mk->kobj, &module_uevent.attr);
736#endif
737 if (err) {
738 kobject_put(&mk->kobj);
739 printk(KERN_ERR
740 "Module '%s' failed add to sysfs, error number %d\n",
741 name, err);
742 printk(KERN_ERR
743 "The system will be unstable now.\n");
744 return NULL;
745 }
746
747 /* So that we hold reference in both cases. */
748 kobject_get(&mk->kobj);
749 }
750
751 return mk;
752}
753
754static void __init kernel_add_sysfs_param(const char *name,
755 struct kernel_param *kparam,
756 unsigned int name_skip)
757{
758 struct module_kobject *mk;
759 int err;
760
761 mk = locate_module_kobject(name);
762 if (!mk)
763 return;
764
765 /* We need to remove old parameters before adding more. */
766 if (mk->mp)
767 sysfs_remove_group(&mk->kobj, &mk->mp->grp);
768
769 /* These should not fail at boot. */
770 err = add_sysfs_param(mk, kparam, kparam->name + name_skip);
771 BUG_ON(err);
772 err = sysfs_create_group(&mk->kobj, &mk->mp->grp);
773 BUG_ON(err);
774 kobject_uevent(&mk->kobj, KOBJ_ADD);
775 kobject_put(&mk->kobj);
776}
777
778/*
779 * param_sysfs_builtin - add contents in /sys/parameters for built-in modules
780 *
781 * Add module_parameters to sysfs for "modules" built into the kernel.
782 *
783 * The "module" name (KBUILD_MODNAME) is stored before a dot, the
784 * "parameter" name is stored behind a dot in kernel_param->name. So,
785 * extract the "module" name for all built-in kernel_param-eters,
786 * and for all who have the same, call kernel_add_sysfs_param.
787 */
788static void __init param_sysfs_builtin(void)
789{
790 struct kernel_param *kp;
791 unsigned int name_len;
792 char modname[MODULE_NAME_LEN];
793
794 for (kp = __start___param; kp < __stop___param; kp++) {
795 char *dot;
796
797 if (kp->perm == 0)
798 continue;
799
800 dot = strchr(kp->name, '.');
801 if (!dot) {
802 /* This happens for core_param() */
803 strcpy(modname, "kernel");
804 name_len = 0;
805 } else {
806 name_len = dot - kp->name + 1;
807 strlcpy(modname, kp->name, name_len);
808 }
809 kernel_add_sysfs_param(modname, kp, name_len);
810 }
811}
812
813ssize_t __modver_version_show(struct module_attribute *mattr,
814 struct module_kobject *mk, char *buf)
815{
816 struct module_version_attribute *vattr =
817 container_of(mattr, struct module_version_attribute, mattr);
818
819 return sprintf(buf, "%s\n", vattr->version);
820}
821
822extern const struct module_version_attribute *__start___modver[];
823extern const struct module_version_attribute *__stop___modver[];
824
825static void __init version_sysfs_builtin(void)
826{
827 const struct module_version_attribute **p;
828 struct module_kobject *mk;
829 int err;
830
831 for (p = __start___modver; p < __stop___modver; p++) {
832 const struct module_version_attribute *vattr = *p;
833
834 mk = locate_module_kobject(vattr->module_name);
835 if (mk) {
836 err = sysfs_create_file(&mk->kobj, &vattr->mattr.attr);
837 kobject_uevent(&mk->kobj, KOBJ_ADD);
838 kobject_put(&mk->kobj);
839 }
840 }
841}
842
843/* module-related sysfs stuff */
844
845static ssize_t module_attr_show(struct kobject *kobj,
846 struct attribute *attr,
847 char *buf)
848{
849 struct module_attribute *attribute;
850 struct module_kobject *mk;
851 int ret;
852
853 attribute = to_module_attr(attr);
854 mk = to_module_kobject(kobj);
855
856 if (!attribute->show)
857 return -EIO;
858
859 ret = attribute->show(attribute, mk, buf);
860
861 return ret;
862}
863
864static ssize_t module_attr_store(struct kobject *kobj,
865 struct attribute *attr,
866 const char *buf, size_t len)
867{
868 struct module_attribute *attribute;
869 struct module_kobject *mk;
870 int ret;
871
872 attribute = to_module_attr(attr);
873 mk = to_module_kobject(kobj);
874
875 if (!attribute->store)
876 return -EIO;
877
878 ret = attribute->store(attribute, mk, buf, len);
879
880 return ret;
881}
882
883static const struct sysfs_ops module_sysfs_ops = {
884 .show = module_attr_show,
885 .store = module_attr_store,
886};
887
888static int uevent_filter(struct kset *kset, struct kobject *kobj)
889{
890 struct kobj_type *ktype = get_ktype(kobj);
891
892 if (ktype == &module_ktype)
893 return 1;
894 return 0;
895}
896
897static const struct kset_uevent_ops module_uevent_ops = {
898 .filter = uevent_filter,
899};
900
901struct kset *module_kset;
902int module_sysfs_initialized;
903
904struct kobj_type module_ktype = {
905 .sysfs_ops = &module_sysfs_ops,
906};
907
908/*
909 * param_sysfs_init - wrapper for built-in params support
910 */
911static int __init param_sysfs_init(void)
912{
913 module_kset = kset_create_and_add("module", &module_uevent_ops, NULL);
914 if (!module_kset) {
915 printk(KERN_WARNING "%s (%d): error creating kset\n",
916 __FILE__, __LINE__);
917 return -ENOMEM;
918 }
919 module_sysfs_initialized = 1;
920
921 version_sysfs_builtin();
922 param_sysfs_builtin();
923
924 return 0;
925}
926subsys_initcall(param_sysfs_init);
927
928#endif /* CONFIG_SYSFS */
1/* Helpers for initial module or kernel cmdline parsing
2 Copyright (C) 2001 Rusty Russell.
3
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2 of the License, or
7 (at your option) any later version.
8
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
13
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17*/
18#include <linux/kernel.h>
19#include <linux/string.h>
20#include <linux/errno.h>
21#include <linux/module.h>
22#include <linux/device.h>
23#include <linux/err.h>
24#include <linux/slab.h>
25#include <linux/ctype.h>
26
27/* Protects all parameters, and incidentally kmalloced_param list. */
28static DEFINE_MUTEX(param_lock);
29
30/* This just allows us to keep track of which parameters are kmalloced. */
31struct kmalloced_param {
32 struct list_head list;
33 char val[];
34};
35static LIST_HEAD(kmalloced_params);
36
37static void *kmalloc_parameter(unsigned int size)
38{
39 struct kmalloced_param *p;
40
41 p = kmalloc(sizeof(*p) + size, GFP_KERNEL);
42 if (!p)
43 return NULL;
44
45 list_add(&p->list, &kmalloced_params);
46 return p->val;
47}
48
49/* Does nothing if parameter wasn't kmalloced above. */
50static void maybe_kfree_parameter(void *param)
51{
52 struct kmalloced_param *p;
53
54 list_for_each_entry(p, &kmalloced_params, list) {
55 if (p->val == param) {
56 list_del(&p->list);
57 kfree(p);
58 break;
59 }
60 }
61}
62
63static char dash2underscore(char c)
64{
65 if (c == '-')
66 return '_';
67 return c;
68}
69
70bool parameqn(const char *a, const char *b, size_t n)
71{
72 size_t i;
73
74 for (i = 0; i < n; i++) {
75 if (dash2underscore(a[i]) != dash2underscore(b[i]))
76 return false;
77 }
78 return true;
79}
80
81bool parameq(const char *a, const char *b)
82{
83 return parameqn(a, b, strlen(a)+1);
84}
85
86static int parse_one(char *param,
87 char *val,
88 const char *doing,
89 const struct kernel_param *params,
90 unsigned num_params,
91 s16 min_level,
92 s16 max_level,
93 int (*handle_unknown)(char *param, char *val,
94 const char *doing))
95{
96 unsigned int i;
97 int err;
98
99 /* Find parameter */
100 for (i = 0; i < num_params; i++) {
101 if (parameq(param, params[i].name)) {
102 if (params[i].level < min_level
103 || params[i].level > max_level)
104 return 0;
105 /* No one handled NULL, so do it here. */
106 if (!val && params[i].ops->set != param_set_bool
107 && params[i].ops->set != param_set_bint)
108 return -EINVAL;
109 pr_debug("handling %s with %p\n", param,
110 params[i].ops->set);
111 mutex_lock(¶m_lock);
112 err = params[i].ops->set(val, ¶ms[i]);
113 mutex_unlock(¶m_lock);
114 return err;
115 }
116 }
117
118 if (handle_unknown) {
119 pr_debug("doing %s: %s='%s'\n", doing, param, val);
120 return handle_unknown(param, val, doing);
121 }
122
123 pr_debug("Unknown argument '%s'\n", param);
124 return -ENOENT;
125}
126
127/* You can use " around spaces, but can't escape ". */
128/* Hyphens and underscores equivalent in parameter names. */
129static char *next_arg(char *args, char **param, char **val)
130{
131 unsigned int i, equals = 0;
132 int in_quote = 0, quoted = 0;
133 char *next;
134
135 if (*args == '"') {
136 args++;
137 in_quote = 1;
138 quoted = 1;
139 }
140
141 for (i = 0; args[i]; i++) {
142 if (isspace(args[i]) && !in_quote)
143 break;
144 if (equals == 0) {
145 if (args[i] == '=')
146 equals = i;
147 }
148 if (args[i] == '"')
149 in_quote = !in_quote;
150 }
151
152 *param = args;
153 if (!equals)
154 *val = NULL;
155 else {
156 args[equals] = '\0';
157 *val = args + equals + 1;
158
159 /* Don't include quotes in value. */
160 if (**val == '"') {
161 (*val)++;
162 if (args[i-1] == '"')
163 args[i-1] = '\0';
164 }
165 if (quoted && args[i-1] == '"')
166 args[i-1] = '\0';
167 }
168
169 if (args[i]) {
170 args[i] = '\0';
171 next = args + i + 1;
172 } else
173 next = args + i;
174
175 /* Chew up trailing spaces. */
176 return skip_spaces(next);
177}
178
179/* Args looks like "foo=bar,bar2 baz=fuz wiz". */
180int parse_args(const char *doing,
181 char *args,
182 const struct kernel_param *params,
183 unsigned num,
184 s16 min_level,
185 s16 max_level,
186 int (*unknown)(char *param, char *val, const char *doing))
187{
188 char *param, *val;
189
190 /* Chew leading spaces */
191 args = skip_spaces(args);
192
193 if (*args)
194 pr_debug("doing %s, parsing ARGS: '%s'\n", doing, args);
195
196 while (*args) {
197 int ret;
198 int irq_was_disabled;
199
200 args = next_arg(args, ¶m, &val);
201 irq_was_disabled = irqs_disabled();
202 ret = parse_one(param, val, doing, params, num,
203 min_level, max_level, unknown);
204 if (irq_was_disabled && !irqs_disabled())
205 pr_warn("%s: option '%s' enabled irq's!\n",
206 doing, param);
207
208 switch (ret) {
209 case -ENOENT:
210 pr_err("%s: Unknown parameter `%s'\n", doing, param);
211 return ret;
212 case -ENOSPC:
213 pr_err("%s: `%s' too large for parameter `%s'\n",
214 doing, val ?: "", param);
215 return ret;
216 case 0:
217 break;
218 default:
219 pr_err("%s: `%s' invalid for parameter `%s'\n",
220 doing, val ?: "", param);
221 return ret;
222 }
223 }
224
225 /* All parsed OK. */
226 return 0;
227}
228
229/* Lazy bastard, eh? */
230#define STANDARD_PARAM_DEF(name, type, format, tmptype, strtolfn) \
231 int param_set_##name(const char *val, const struct kernel_param *kp) \
232 { \
233 tmptype l; \
234 int ret; \
235 \
236 ret = strtolfn(val, 0, &l); \
237 if (ret < 0 || ((type)l != l)) \
238 return ret < 0 ? ret : -EINVAL; \
239 *((type *)kp->arg) = l; \
240 return 0; \
241 } \
242 int param_get_##name(char *buffer, const struct kernel_param *kp) \
243 { \
244 return sprintf(buffer, format, *((type *)kp->arg)); \
245 } \
246 struct kernel_param_ops param_ops_##name = { \
247 .set = param_set_##name, \
248 .get = param_get_##name, \
249 }; \
250 EXPORT_SYMBOL(param_set_##name); \
251 EXPORT_SYMBOL(param_get_##name); \
252 EXPORT_SYMBOL(param_ops_##name)
253
254
255STANDARD_PARAM_DEF(byte, unsigned char, "%c", unsigned long, strict_strtoul);
256STANDARD_PARAM_DEF(short, short, "%hi", long, strict_strtol);
257STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", unsigned long, strict_strtoul);
258STANDARD_PARAM_DEF(int, int, "%i", long, strict_strtol);
259STANDARD_PARAM_DEF(uint, unsigned int, "%u", unsigned long, strict_strtoul);
260STANDARD_PARAM_DEF(long, long, "%li", long, strict_strtol);
261STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", unsigned long, strict_strtoul);
262
263int param_set_charp(const char *val, const struct kernel_param *kp)
264{
265 if (strlen(val) > 1024) {
266 pr_err("%s: string parameter too long\n", kp->name);
267 return -ENOSPC;
268 }
269
270 maybe_kfree_parameter(*(char **)kp->arg);
271
272 /* This is a hack. We can't kmalloc in early boot, and we
273 * don't need to; this mangled commandline is preserved. */
274 if (slab_is_available()) {
275 *(char **)kp->arg = kmalloc_parameter(strlen(val)+1);
276 if (!*(char **)kp->arg)
277 return -ENOMEM;
278 strcpy(*(char **)kp->arg, val);
279 } else
280 *(const char **)kp->arg = val;
281
282 return 0;
283}
284EXPORT_SYMBOL(param_set_charp);
285
286int param_get_charp(char *buffer, const struct kernel_param *kp)
287{
288 return sprintf(buffer, "%s", *((char **)kp->arg));
289}
290EXPORT_SYMBOL(param_get_charp);
291
292static void param_free_charp(void *arg)
293{
294 maybe_kfree_parameter(*((char **)arg));
295}
296
297struct kernel_param_ops param_ops_charp = {
298 .set = param_set_charp,
299 .get = param_get_charp,
300 .free = param_free_charp,
301};
302EXPORT_SYMBOL(param_ops_charp);
303
304/* Actually could be a bool or an int, for historical reasons. */
305int param_set_bool(const char *val, const struct kernel_param *kp)
306{
307 /* No equals means "set"... */
308 if (!val) val = "1";
309
310 /* One of =[yYnN01] */
311 return strtobool(val, kp->arg);
312}
313EXPORT_SYMBOL(param_set_bool);
314
315int param_get_bool(char *buffer, const struct kernel_param *kp)
316{
317 /* Y and N chosen as being relatively non-coder friendly */
318 return sprintf(buffer, "%c", *(bool *)kp->arg ? 'Y' : 'N');
319}
320EXPORT_SYMBOL(param_get_bool);
321
322struct kernel_param_ops param_ops_bool = {
323 .set = param_set_bool,
324 .get = param_get_bool,
325};
326EXPORT_SYMBOL(param_ops_bool);
327
328/* This one must be bool. */
329int param_set_invbool(const char *val, const struct kernel_param *kp)
330{
331 int ret;
332 bool boolval;
333 struct kernel_param dummy;
334
335 dummy.arg = &boolval;
336 ret = param_set_bool(val, &dummy);
337 if (ret == 0)
338 *(bool *)kp->arg = !boolval;
339 return ret;
340}
341EXPORT_SYMBOL(param_set_invbool);
342
343int param_get_invbool(char *buffer, const struct kernel_param *kp)
344{
345 return sprintf(buffer, "%c", (*(bool *)kp->arg) ? 'N' : 'Y');
346}
347EXPORT_SYMBOL(param_get_invbool);
348
349struct kernel_param_ops param_ops_invbool = {
350 .set = param_set_invbool,
351 .get = param_get_invbool,
352};
353EXPORT_SYMBOL(param_ops_invbool);
354
355int param_set_bint(const char *val, const struct kernel_param *kp)
356{
357 struct kernel_param boolkp;
358 bool v;
359 int ret;
360
361 /* Match bool exactly, by re-using it. */
362 boolkp = *kp;
363 boolkp.arg = &v;
364
365 ret = param_set_bool(val, &boolkp);
366 if (ret == 0)
367 *(int *)kp->arg = v;
368 return ret;
369}
370EXPORT_SYMBOL(param_set_bint);
371
372struct kernel_param_ops param_ops_bint = {
373 .set = param_set_bint,
374 .get = param_get_int,
375};
376EXPORT_SYMBOL(param_ops_bint);
377
378/* We break the rule and mangle the string. */
379static int param_array(const char *name,
380 const char *val,
381 unsigned int min, unsigned int max,
382 void *elem, int elemsize,
383 int (*set)(const char *, const struct kernel_param *kp),
384 s16 level,
385 unsigned int *num)
386{
387 int ret;
388 struct kernel_param kp;
389 char save;
390
391 /* Get the name right for errors. */
392 kp.name = name;
393 kp.arg = elem;
394 kp.level = level;
395
396 *num = 0;
397 /* We expect a comma-separated list of values. */
398 do {
399 int len;
400
401 if (*num == max) {
402 pr_err("%s: can only take %i arguments\n", name, max);
403 return -EINVAL;
404 }
405 len = strcspn(val, ",");
406
407 /* nul-terminate and parse */
408 save = val[len];
409 ((char *)val)[len] = '\0';
410 BUG_ON(!mutex_is_locked(¶m_lock));
411 ret = set(val, &kp);
412
413 if (ret != 0)
414 return ret;
415 kp.arg += elemsize;
416 val += len+1;
417 (*num)++;
418 } while (save == ',');
419
420 if (*num < min) {
421 pr_err("%s: needs at least %i arguments\n", name, min);
422 return -EINVAL;
423 }
424 return 0;
425}
426
427static int param_array_set(const char *val, const struct kernel_param *kp)
428{
429 const struct kparam_array *arr = kp->arr;
430 unsigned int temp_num;
431
432 return param_array(kp->name, val, 1, arr->max, arr->elem,
433 arr->elemsize, arr->ops->set, kp->level,
434 arr->num ?: &temp_num);
435}
436
437static int param_array_get(char *buffer, const struct kernel_param *kp)
438{
439 int i, off, ret;
440 const struct kparam_array *arr = kp->arr;
441 struct kernel_param p;
442
443 p = *kp;
444 for (i = off = 0; i < (arr->num ? *arr->num : arr->max); i++) {
445 if (i)
446 buffer[off++] = ',';
447 p.arg = arr->elem + arr->elemsize * i;
448 BUG_ON(!mutex_is_locked(¶m_lock));
449 ret = arr->ops->get(buffer + off, &p);
450 if (ret < 0)
451 return ret;
452 off += ret;
453 }
454 buffer[off] = '\0';
455 return off;
456}
457
458static void param_array_free(void *arg)
459{
460 unsigned int i;
461 const struct kparam_array *arr = arg;
462
463 if (arr->ops->free)
464 for (i = 0; i < (arr->num ? *arr->num : arr->max); i++)
465 arr->ops->free(arr->elem + arr->elemsize * i);
466}
467
468struct kernel_param_ops param_array_ops = {
469 .set = param_array_set,
470 .get = param_array_get,
471 .free = param_array_free,
472};
473EXPORT_SYMBOL(param_array_ops);
474
475int param_set_copystring(const char *val, const struct kernel_param *kp)
476{
477 const struct kparam_string *kps = kp->str;
478
479 if (strlen(val)+1 > kps->maxlen) {
480 pr_err("%s: string doesn't fit in %u chars.\n",
481 kp->name, kps->maxlen-1);
482 return -ENOSPC;
483 }
484 strcpy(kps->string, val);
485 return 0;
486}
487EXPORT_SYMBOL(param_set_copystring);
488
489int param_get_string(char *buffer, const struct kernel_param *kp)
490{
491 const struct kparam_string *kps = kp->str;
492 return strlcpy(buffer, kps->string, kps->maxlen);
493}
494EXPORT_SYMBOL(param_get_string);
495
496struct kernel_param_ops param_ops_string = {
497 .set = param_set_copystring,
498 .get = param_get_string,
499};
500EXPORT_SYMBOL(param_ops_string);
501
502/* sysfs output in /sys/modules/XYZ/parameters/ */
503#define to_module_attr(n) container_of(n, struct module_attribute, attr)
504#define to_module_kobject(n) container_of(n, struct module_kobject, kobj)
505
506extern struct kernel_param __start___param[], __stop___param[];
507
508struct param_attribute
509{
510 struct module_attribute mattr;
511 const struct kernel_param *param;
512};
513
514struct module_param_attrs
515{
516 unsigned int num;
517 struct attribute_group grp;
518 struct param_attribute attrs[0];
519};
520
521#ifdef CONFIG_SYSFS
522#define to_param_attr(n) container_of(n, struct param_attribute, mattr)
523
524static ssize_t param_attr_show(struct module_attribute *mattr,
525 struct module_kobject *mk, char *buf)
526{
527 int count;
528 struct param_attribute *attribute = to_param_attr(mattr);
529
530 if (!attribute->param->ops->get)
531 return -EPERM;
532
533 mutex_lock(¶m_lock);
534 count = attribute->param->ops->get(buf, attribute->param);
535 mutex_unlock(¶m_lock);
536 if (count > 0) {
537 strcat(buf, "\n");
538 ++count;
539 }
540 return count;
541}
542
543/* sysfs always hands a nul-terminated string in buf. We rely on that. */
544static ssize_t param_attr_store(struct module_attribute *mattr,
545 struct module_kobject *km,
546 const char *buf, size_t len)
547{
548 int err;
549 struct param_attribute *attribute = to_param_attr(mattr);
550
551 if (!attribute->param->ops->set)
552 return -EPERM;
553
554 mutex_lock(¶m_lock);
555 err = attribute->param->ops->set(buf, attribute->param);
556 mutex_unlock(¶m_lock);
557 if (!err)
558 return len;
559 return err;
560}
561#endif
562
563#ifdef CONFIG_MODULES
564#define __modinit
565#else
566#define __modinit __init
567#endif
568
569#ifdef CONFIG_SYSFS
570void __kernel_param_lock(void)
571{
572 mutex_lock(¶m_lock);
573}
574EXPORT_SYMBOL(__kernel_param_lock);
575
576void __kernel_param_unlock(void)
577{
578 mutex_unlock(¶m_lock);
579}
580EXPORT_SYMBOL(__kernel_param_unlock);
581
582/*
583 * add_sysfs_param - add a parameter to sysfs
584 * @mk: struct module_kobject
585 * @kparam: the actual parameter definition to add to sysfs
586 * @name: name of parameter
587 *
588 * Create a kobject if for a (per-module) parameter if mp NULL, and
589 * create file in sysfs. Returns an error on out of memory. Always cleans up
590 * if there's an error.
591 */
592static __modinit int add_sysfs_param(struct module_kobject *mk,
593 const struct kernel_param *kp,
594 const char *name)
595{
596 struct module_param_attrs *new;
597 struct attribute **attrs;
598 int err, num;
599
600 /* We don't bother calling this with invisible parameters. */
601 BUG_ON(!kp->perm);
602
603 if (!mk->mp) {
604 num = 0;
605 attrs = NULL;
606 } else {
607 num = mk->mp->num;
608 attrs = mk->mp->grp.attrs;
609 }
610
611 /* Enlarge. */
612 new = krealloc(mk->mp,
613 sizeof(*mk->mp) + sizeof(mk->mp->attrs[0]) * (num+1),
614 GFP_KERNEL);
615 if (!new) {
616 kfree(mk->mp);
617 err = -ENOMEM;
618 goto fail;
619 }
620 attrs = krealloc(attrs, sizeof(new->grp.attrs[0])*(num+2), GFP_KERNEL);
621 if (!attrs) {
622 err = -ENOMEM;
623 goto fail_free_new;
624 }
625
626 /* Sysfs wants everything zeroed. */
627 memset(new, 0, sizeof(*new));
628 memset(&new->attrs[num], 0, sizeof(new->attrs[num]));
629 memset(&attrs[num], 0, sizeof(attrs[num]));
630 new->grp.name = "parameters";
631 new->grp.attrs = attrs;
632
633 /* Tack new one on the end. */
634 sysfs_attr_init(&new->attrs[num].mattr.attr);
635 new->attrs[num].param = kp;
636 new->attrs[num].mattr.show = param_attr_show;
637 new->attrs[num].mattr.store = param_attr_store;
638 new->attrs[num].mattr.attr.name = (char *)name;
639 new->attrs[num].mattr.attr.mode = kp->perm;
640 new->num = num+1;
641
642 /* Fix up all the pointers, since krealloc can move us */
643 for (num = 0; num < new->num; num++)
644 new->grp.attrs[num] = &new->attrs[num].mattr.attr;
645 new->grp.attrs[num] = NULL;
646
647 mk->mp = new;
648 return 0;
649
650fail_free_new:
651 kfree(new);
652fail:
653 mk->mp = NULL;
654 return err;
655}
656
657#ifdef CONFIG_MODULES
658static void free_module_param_attrs(struct module_kobject *mk)
659{
660 kfree(mk->mp->grp.attrs);
661 kfree(mk->mp);
662 mk->mp = NULL;
663}
664
665/*
666 * module_param_sysfs_setup - setup sysfs support for one module
667 * @mod: module
668 * @kparam: module parameters (array)
669 * @num_params: number of module parameters
670 *
671 * Adds sysfs entries for module parameters under
672 * /sys/module/[mod->name]/parameters/
673 */
674int module_param_sysfs_setup(struct module *mod,
675 const struct kernel_param *kparam,
676 unsigned int num_params)
677{
678 int i, err;
679 bool params = false;
680
681 for (i = 0; i < num_params; i++) {
682 if (kparam[i].perm == 0)
683 continue;
684 err = add_sysfs_param(&mod->mkobj, &kparam[i], kparam[i].name);
685 if (err)
686 return err;
687 params = true;
688 }
689
690 if (!params)
691 return 0;
692
693 /* Create the param group. */
694 err = sysfs_create_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
695 if (err)
696 free_module_param_attrs(&mod->mkobj);
697 return err;
698}
699
700/*
701 * module_param_sysfs_remove - remove sysfs support for one module
702 * @mod: module
703 *
704 * Remove sysfs entries for module parameters and the corresponding
705 * kobject.
706 */
707void module_param_sysfs_remove(struct module *mod)
708{
709 if (mod->mkobj.mp) {
710 sysfs_remove_group(&mod->mkobj.kobj, &mod->mkobj.mp->grp);
711 /* We are positive that no one is using any param
712 * attrs at this point. Deallocate immediately. */
713 free_module_param_attrs(&mod->mkobj);
714 }
715}
716#endif
717
718void destroy_params(const struct kernel_param *params, unsigned num)
719{
720 unsigned int i;
721
722 for (i = 0; i < num; i++)
723 if (params[i].ops->free)
724 params[i].ops->free(params[i].arg);
725}
726
727static struct module_kobject * __init locate_module_kobject(const char *name)
728{
729 struct module_kobject *mk;
730 struct kobject *kobj;
731 int err;
732
733 kobj = kset_find_obj(module_kset, name);
734 if (kobj) {
735 mk = to_module_kobject(kobj);
736 } else {
737 mk = kzalloc(sizeof(struct module_kobject), GFP_KERNEL);
738 BUG_ON(!mk);
739
740 mk->mod = THIS_MODULE;
741 mk->kobj.kset = module_kset;
742 err = kobject_init_and_add(&mk->kobj, &module_ktype, NULL,
743 "%s", name);
744#ifdef CONFIG_MODULES
745 if (!err)
746 err = sysfs_create_file(&mk->kobj, &module_uevent.attr);
747#endif
748 if (err) {
749 kobject_put(&mk->kobj);
750 pr_crit("Adding module '%s' to sysfs failed (%d), the system may be unstable.\n",
751 name, err);
752 return NULL;
753 }
754
755 /* So that we hold reference in both cases. */
756 kobject_get(&mk->kobj);
757 }
758
759 return mk;
760}
761
762static void __init kernel_add_sysfs_param(const char *name,
763 struct kernel_param *kparam,
764 unsigned int name_skip)
765{
766 struct module_kobject *mk;
767 int err;
768
769 mk = locate_module_kobject(name);
770 if (!mk)
771 return;
772
773 /* We need to remove old parameters before adding more. */
774 if (mk->mp)
775 sysfs_remove_group(&mk->kobj, &mk->mp->grp);
776
777 /* These should not fail at boot. */
778 err = add_sysfs_param(mk, kparam, kparam->name + name_skip);
779 BUG_ON(err);
780 err = sysfs_create_group(&mk->kobj, &mk->mp->grp);
781 BUG_ON(err);
782 kobject_uevent(&mk->kobj, KOBJ_ADD);
783 kobject_put(&mk->kobj);
784}
785
786/*
787 * param_sysfs_builtin - add contents in /sys/parameters for built-in modules
788 *
789 * Add module_parameters to sysfs for "modules" built into the kernel.
790 *
791 * The "module" name (KBUILD_MODNAME) is stored before a dot, the
792 * "parameter" name is stored behind a dot in kernel_param->name. So,
793 * extract the "module" name for all built-in kernel_param-eters,
794 * and for all who have the same, call kernel_add_sysfs_param.
795 */
796static void __init param_sysfs_builtin(void)
797{
798 struct kernel_param *kp;
799 unsigned int name_len;
800 char modname[MODULE_NAME_LEN];
801
802 for (kp = __start___param; kp < __stop___param; kp++) {
803 char *dot;
804
805 if (kp->perm == 0)
806 continue;
807
808 dot = strchr(kp->name, '.');
809 if (!dot) {
810 /* This happens for core_param() */
811 strcpy(modname, "kernel");
812 name_len = 0;
813 } else {
814 name_len = dot - kp->name + 1;
815 strlcpy(modname, kp->name, name_len);
816 }
817 kernel_add_sysfs_param(modname, kp, name_len);
818 }
819}
820
821ssize_t __modver_version_show(struct module_attribute *mattr,
822 struct module_kobject *mk, char *buf)
823{
824 struct module_version_attribute *vattr =
825 container_of(mattr, struct module_version_attribute, mattr);
826
827 return sprintf(buf, "%s\n", vattr->version);
828}
829
830extern const struct module_version_attribute *__start___modver[];
831extern const struct module_version_attribute *__stop___modver[];
832
833static void __init version_sysfs_builtin(void)
834{
835 const struct module_version_attribute **p;
836 struct module_kobject *mk;
837 int err;
838
839 for (p = __start___modver; p < __stop___modver; p++) {
840 const struct module_version_attribute *vattr = *p;
841
842 mk = locate_module_kobject(vattr->module_name);
843 if (mk) {
844 err = sysfs_create_file(&mk->kobj, &vattr->mattr.attr);
845 kobject_uevent(&mk->kobj, KOBJ_ADD);
846 kobject_put(&mk->kobj);
847 }
848 }
849}
850
851/* module-related sysfs stuff */
852
853static ssize_t module_attr_show(struct kobject *kobj,
854 struct attribute *attr,
855 char *buf)
856{
857 struct module_attribute *attribute;
858 struct module_kobject *mk;
859 int ret;
860
861 attribute = to_module_attr(attr);
862 mk = to_module_kobject(kobj);
863
864 if (!attribute->show)
865 return -EIO;
866
867 ret = attribute->show(attribute, mk, buf);
868
869 return ret;
870}
871
872static ssize_t module_attr_store(struct kobject *kobj,
873 struct attribute *attr,
874 const char *buf, size_t len)
875{
876 struct module_attribute *attribute;
877 struct module_kobject *mk;
878 int ret;
879
880 attribute = to_module_attr(attr);
881 mk = to_module_kobject(kobj);
882
883 if (!attribute->store)
884 return -EIO;
885
886 ret = attribute->store(attribute, mk, buf, len);
887
888 return ret;
889}
890
891static const struct sysfs_ops module_sysfs_ops = {
892 .show = module_attr_show,
893 .store = module_attr_store,
894};
895
896static int uevent_filter(struct kset *kset, struct kobject *kobj)
897{
898 struct kobj_type *ktype = get_ktype(kobj);
899
900 if (ktype == &module_ktype)
901 return 1;
902 return 0;
903}
904
905static const struct kset_uevent_ops module_uevent_ops = {
906 .filter = uevent_filter,
907};
908
909struct kset *module_kset;
910int module_sysfs_initialized;
911
912struct kobj_type module_ktype = {
913 .sysfs_ops = &module_sysfs_ops,
914};
915
916/*
917 * param_sysfs_init - wrapper for built-in params support
918 */
919static int __init param_sysfs_init(void)
920{
921 module_kset = kset_create_and_add("module", &module_uevent_ops, NULL);
922 if (!module_kset) {
923 printk(KERN_WARNING "%s (%d): error creating kset\n",
924 __FILE__, __LINE__);
925 return -ENOMEM;
926 }
927 module_sysfs_initialized = 1;
928
929 version_sysfs_builtin();
930 param_sysfs_builtin();
931
932 return 0;
933}
934subsys_initcall(param_sysfs_init);
935
936#endif /* CONFIG_SYSFS */